SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '0a5a29b753ccdb8d4fe041db18fc9635ea7f67cb56fad03dfc8ab5a3961e06ca' 
  AND token = 'sjHfgOmSxcSfptfU3Sb0uXPJCRxkRDRpDr3OE9vPPxs=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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