SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'cd57e31896e74d8f578ac4f337e57bd43ec926d798e86c087cb6a9ad9c137b09' 
  AND token = 'IhW/tVAtAuQw18sCWJJGnm+NtLZ0KYrDmq5O3Mkxl6s=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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