SELECT 
  1 
FROM 
  cscart_aprillock_keys 
WHERE 
  key_id = '6eda5e10d7cbaedb8e29463a51df9568eaf48886c63d453fbf14e25e7830f408' 
  AND token = 'DEDcxQuMLtoalS7nzH7X26p7lv2lb3vbBy9dLBNEMyY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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