SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dca2ed243f28382a4bad9a0115b31d25e6af45dc123bc9456f448396d14ae199' 
  AND token = 'Lkt1BnfysyxedUzESHTfQ1AYwaCEMJaUMy91svvqrok=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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