SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '8506cc9681c10f92280abcf3ffe0cc29c3fdfd27838819d40c21ba6823210641' 
  AND token = 'TeNf2A0zZtB1vjAHfK7yyWyrLcfoXsVcysJLVr2CYAo=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

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