SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '2506b51b4d7c873b2793851c42ce5f3f10e6726780c4f3c920bab1515beb0097' 
  AND token = 'qqvGoJKZ79KxvlXUwp1Pw/9LSW0+ev61h5AavEM91VI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00021

JSON explain

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