SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0c7cbe8a58196fbb6be911fc715286d01b4cdcd27dcdfc5c11b810f0ca3aaa95' 
  AND token = '94fuHWdbwzPdjAct5em0c9NY+pcJf5G4Gq45GbeBZM4=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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