SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '7f7c764f240fd55ce4320eafb2e7c4a116abc75d93753b55773a6eae2ffa5724' 
  AND token = 'iNJh5vsIatlS5MxFRR5QnMpqyxQIKzwL1HJXJwXJWVw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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