SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ee9fb646d3c47ac0f068377f46e9fc71e443430971144d8e48977443be638d8b' 
  AND token = 'Vzi2WBRP02J0m1ZUsl5fyLGpek0SrWIIR0Tzldlo/6c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

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