SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '173c3b3724aebf657a12f2485505a9198517986d91d33453bcd28008d3d0179c' 
  AND token = 'k/zKczRsaYZpP15eY4g65m50Y3wkBLr6r1X1fqtqJGU=' 
  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"
    }
  }
}