SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '39bfc24e374a9a97b37c856d2076b43bf3bcd8ef682f70a19ab24dbad945b64a' 
  AND token = '/JEoRZ7GqVM7Jg2EkL1sBI9SeB1nTB6+ErURzPixNYQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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