SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b5aaa22ca382564ec191c8b35fbe93941d56bde06492528d83ab8bbe062899ae' 
  AND token = 'xcFJ05NrHC1u5kvyp3SO0/rQxNZfEQGj2/5gOHNqtBs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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