SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a4d5cb66a5771f170efe2238c55149431b425c962c9888835349923d6b495011' 
  AND token = 'gEq3Y4kmI6hnWz19iExwvOtW9Lg7y45+optTrYuqwNY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00054

JSON explain

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