SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '5fed1c23bd40fbe008f3904b8efdbcd627f31a4ecdc1879fccaf3ef40ce81b01' 
  AND token = '3S0I0OjKsUkx3OmlcUZAuak1aEKTXt0H704ogIBFmgM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00051

JSON explain

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