SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = 'ea8143d78a0e86c5bd55530df9add25d40de877b2288f3ad57497277eb0612c5' 
  AND token = '7H4GnFakIPCVNJQuLNYYKSjVV3kZj1hNNF9nf9pSDt0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00022

JSON explain

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