SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7499300fa5e57523fa62dd991d6ec52ee46c2da4ff657916ef1c90234f83e010' 
  AND token = 'L+InWsWBfAB2NH5i/d0mjpOAClqA6vcNgKTHBhfGFjQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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