SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'a9401a95936d223cf8b715cc46dd6d415be982f3ce19804d6e025d43af657772' 
  AND token = '69g+ReE+8izE7RPcmCYdGGIdtpPJmzW5/MHw2kmkMAY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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