SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '544aaf14d4db9ed38719126381a69193b891f9b0b3b23160e25793f4b663da0e' 
  AND token = 'GhuIHkaVeCObRYEPiZFLNW3vPZEDSWHLOy7g2Q/sSug=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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