SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '6199e644faf881e6d239e65930421bf50b553f58d19aa0eb4b79bc3ac250716e' 
  AND token = 'BEEAvTgnVIjPVrc/QWgVFtSejT4fgF4T0BAHQ2uoivc=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}