SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c2d6976db9a42ff6b36f40363c658857fbebafe98b1628fd318c258220ddc87e' 
  AND token = 'BGZkeImDoNxHA1kfTR6cE/Ix0guCF+Iz6MVU1UCmipI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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