SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '117d2c6236c5e2324f6b0caaa5b6db1fd06382d3ecd08b459866436c2150fe05' 
  AND token = 'FmgbjEXJZFHU2ZnziWc/ECMAqCfSSmbmoJa5Z4tZFXo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00093

JSON explain

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