SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'aecbe4eff34e2f70737ed556b7737e3f54b68100b5de744bedc27967492b3020' 
  AND token = 'K/q6NHX3PDHMd33JJmngXYbMcHeVkgzRYTYDWuwuOwY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00042

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}