SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'c7ce0f5c3248aac899ba5cab023bd85a4d186bcae2f675d5e9d7455e697c1731' 
  AND token = 'tkKw/xKitTSh4OpKsl8HDoOHVB8CIUN8mavFltuYijY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00031

JSON explain

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