SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '448555664ff7c99938f059b1a312e417e321fa855b1341dc6d89273563575bab' 
  AND token = 'oJFpwFWMRUjJqpqIEc5jCl5WBeUj6CBu+TQqJUP4I5c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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