SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '26437693a184163a8ee13f492c6454165fd81165b13679c669934673268045fb' 
  AND token = 'dj0WiqrSVP5KUlSKEy2j7U7hCIDGsKiRH6TPVGQ7Mhk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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