SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '1d7196f60ca6436d11d3dbfa87ef0bb83adf03e655fc16b2deb9dd0ccecb299c' 
  AND token = 'dpOcwWi+Ew5QNWk/TDembVdQ162mj37etTfgLSGMAdw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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