SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'faf555703a2756f22fc188691efeda6b449fbf5b680f678bdbae0596b8a20dfe' 
  AND token = 'OsCqBOwpA/DtBqVmowEId9RvBHV/rgmq4CkUzJQnLVE=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

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