SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e8066e2cc67324716ad621055f34812eac9c8aa704d97ff3ceaaeb8361c39cdb' 
  AND token = '8jF8wjoAnJTTxlPtDRDlBX/D7QUmHRCvWw1CMRdFlHw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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