SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c0e358cdc1115808d5c46c4f707bce0e41ebc214d6e92576d074fdec56d01721' 
  AND token = 'v9FcnLe6c2rVyqOZmt+3kg90LoywifPk5BeasSGT6ts=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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