SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9933a5cbf4f3964e68ad81f87bb5975867558466d28eac55155d800ef8f55736' 
  AND token = 'EMWYGp5KWnp1BIBoYIEpHlmEgLzD4RrIrXnreIgD2CA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00052

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}