SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '3bcac1e9c304d831df0562d0e66e6b36839648d278b7666d9245da06d9935d45' 
  AND token = '3Gxwn1w5COJaVnA+N321T9E7vbaPqf1ln1AlMXGUguk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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