SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a3473121a2c2987a5d59da63ed69f91a1ce1b92116e94303508532a1040a7edc' 
  AND token = 'ntDormZLSFq/T7KmREfFztxyG62KfjVZKk39Gwgu894=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00046

JSON explain

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