SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f701e7279e5541c75f2c49f327c62cad25d437a6ce5cfe36fe793df703d5d99d' 
  AND token = 'YcphSSgdy1Ss23K1fQcezLFk81afVehYFAo5NoQ1VPI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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