SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'e9340a62b1a845f3ee643b5bc655208f19040de46f5175e01447630fcf5804f1' 
  AND token = 'sHLKKd8lTUjUcVmoGNxTqh+B2uV+kQgLNvH4CgAFQZg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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