SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'd94f9fa047d1e67db4cf381d54173b707189621f2d2a239ab22bbac2c66511eb' 
  AND token = 'heU2eEMN4dyAGAuD2sAqd3HwhEdO4J6pdQpp/loG2Z0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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