SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'c67e731da88c2ac7cfb858273a51e877825ad3dd101382a18dfd90d4f8dd953c' 
  AND token = 'zx+EhjMFG6nYnelrJuStvshJqLjG7zWUeRdV319pegU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00037

JSON explain

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