SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '41aa368ff80fe6c305a8d0e35724ea7f45dc8cd2ca797921daf9fb3cc373a891' 
  AND token = 'rGUqjl6vw/kpoGtF2FjsvCJtrMVWULFN5Aspv6JmnD4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00038

JSON explain

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