SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b142eba60495bb0eba88967ec2c0433cab2b689401e8b1fc05de092796fb56d4' 
  AND token = 'EaDOzmjlyhr+vCGnumCjuyAUH/maIIHY+Vgku6aFTcQ=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00041

JSON explain

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