SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '466f452ebd1f01cf8a5e0e975f5ef692edc64678d44e6628b6b31d637580fc0e' 
  AND token = 'vfvK42Akg7GieosEkmipVb9bmwPw5FhBaF032gojoa8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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