SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9c25e07dde402aef3d3466fefa80cab789cb29647dd0f855c5f03670abef7b1d' 
  AND token = 'LqIzX72gRIDtbT3EcUP/WOng56vmNUEXClBfc0eKnbY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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