SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd201da239619f6caef6ea943c546faadb013cd4e65f8beda5770f427762fa14c' 
  AND token = 'Y28axO/aT2neUWYGLRux4YE1MleOF7DOqim9SLpZJQk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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