SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '4b3100a158df03c3c6db3a5f7bca30437850d25ce20ad7a91226a480ebadfc23' 
  AND token = 'sYUmcWV44cJyJzeb0F+hHyNrW4XC9/thq8PKbBXm6Mk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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