SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'b5838d29fcb092b46165eace73457b8645161d8a01a84bad6122613d026e45c2' 
  AND token = 'eUU8GjG82gCLHnrRKz2O77uwp+8HpF3wF5I7V+2yjrg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00020

JSON explain

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